Lewis buewell mcdonald



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L. B. MGDONALD.

FIRE ESGAPB.

No.y 310,603.

Patented Jn. 13,1885.

INVBNTOR of@ ffm WTNESSES QW ZM ATTORNEYS.

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LEI/VIS BIIRVELL MODONALD, OF LITTLE ROCK, ARKANSAS.

Flan-ESCAPE.

SPECIFICATION forming part of Letters Patent No. 310,603, dated January 13, 1885.

App'ication filed April 1G, 1884.

To @ZZ whom it may concern:

Be it known that I, LEWIS B. MoDoNALD, of Little Rock, in the county of Pulaski and State of Arkansas, have invented a new and Improved Fire-Escape, of which the following is a full, clear, and exact description.

This invention pertains to improvements in fire-escapes, having for its object to effect the ready and convenient adjustment of the de` vice for use, to enable the safe descent of the escaping person, and to control the speed of descent while causing the automatic recoiling of the safety rope or cable after the descent of one person to permit the escape or descent of another; and the invention consists of the combination of parts and their construction, substantially as hereinafter fully set forth, and pointed out in the claims.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similarletters of reference indicate corresponding parts in all the figures.

Figure l is a perspective view of my improved iire-escape, showing the manner in which it is fastened to the wall of the room. Fig. 2' is aside view of the hollow drum, parts being broken out and others shown in section. Fig. 3 is a cross-sectional elevation ofthe drum.

An L-shaped rod, A, has its lower end passed into a socket formed in a plate, B, secured on the iloor adjoining the wall and below the window-sill, and the upright part of the said rod passes through an eye, C, secured on the bottom piece of the window-casing, the said rod thus being held in such a manner that it can turn on the aXis of the vertical part of the rod. Onthe end of the horizontal part of the rod a horizontal fork, D, is formed, between the prongs of which a circular casing, E, is held, the ends of the transverse axle or shaft F of the casing being held rigidly in the sides of the prongs of the fork. Vithin the hollow drum or circular casing ahollow flanged pulley, G, is mounted loosely on the shaft, and in the hollow pulley G is held a spiral spring, H, one end of which is secured to the shaft F and the other end is secured to the inner surface of the rim of the hollow pulley G. On the outer surface of the rim of the hollow pulley one end of arope, J, is secured, which rope is wound on the pulley and passes through an opening, I, in the circular casing E. Blocks (No model.)

K, secured on the sidesof the casing E, rest against the bottom edges of the prongs of the fork D, thus preventing the casing Etfrom revolving. Ina recess in one of the outer sides of the pulley G a ratchet-wheel, L, is loosely mounted on the shaft F, and with the teeth of the said ratchet-wheel a pawl, M, pivoted on the pulley G, engages,which is pressed against the teeth by a spring, M', the pawl being piyoted to the outer side of the pulley G. A star-wheel, N, is secured to or made integral with the outer surface of the ratchet-wheelL. A weighted or pendulous pawl,O,is pivoted to the inner surface of one of the sides ofthe casing E at the top, which pawl is provided with teeth Oan d O2, adapted to engage with the ends ofthe teeth of the starwheel. A rubber bumper, P, is secured on the rope J a short distance from its free end. A belt, Q, or like device is held in the free end of the rope. In place of the rope a Wire or fine cable can be used.

The operation is as follows: The rope is wound on the pulley G, and the casing E 1s swung against the inner surface of the Wall at the side of the window, as shown in Fig. 1. If the fire-escape is to be used, the horizontal part of the rod A is swung out of the window,

as shown in dotted lines. The strap or belt Q is passed around the body of the person to be rescued, and if the person steps out of the window he will descend, the rope J uncoiling from the pulley G and revolving the same in the direction of the arrow c. The pawl M causes the ratchet-wheel L and star-wheel N to revolve with the pulley, and, as the ends of the teeth of the star-wheel N strike against the teeth O and O2 of the pawl O, the pulley is prevented from revolving too rapidly. The spring H is coiled by the unwinding of the rope. Vhen the person arrives at the ground, he unfastens the belt and releases the rope. The spring I-I uncoils and revolves the pulley G in the inverse direction of the arrow a', and the pawl M slides over the teeth of the ratchetwheel L, which is held by the pawl O. The rope is thus wound on the pulley, and the iireescape can be used by another person.

Having thus described my invention, Iclaim as new and desire to secure by Letters Patentl. In a lire-escape, the combination, with IOO the bifurcated L-shaped rod pivoted to the floor and the window-sill, of a rope pulley or drum pivoted between and in the prongs or arms of the said rod, substantially as herein vshown and described.

2. In a fire-escape, the combination, with the pivoted rod A, having a fork, D, formed on its end, of the casing E, held between the prongs ofthe fork, a spring-pulley contained in the easing, a rope secured on the springpulley, and of the blocks K, secured to the sides of the easing, substantially as herein shown and described.

3. In a fire-escape, the conlbination, with the casing E, having a Xed shaft, F, of the hollow pulley G, mounted on the shaft F, the spring II, contained in the pulley G, and having one end secured to the pulley and the other on the shaft, and the ratchet-wheel L, mounted loosely on the shaft,the pawl M,engagin g with the teeth of the ratchet-wheel and pivoted on the pulley, and of means for holding the l ratchet-Wheel and preventing` it froln revolving too fast when the rope is being nnwound from the pulley, substantially as herein showin and described.

4. In a lire-escape, the combination, with 25 the casing E, having a fixed shaft, F, of the hollow pulley G, mounted loosely on the shaft, the spring II, contained in the pulley G, and having one end secured to the pulley and the other to the shaft, the ratchet-Wheel L, mounted loosely on the shaft F, the paWl M, the star- Wheel N, united With or made integral With the ratchet-Wheel L, and of the pendulous pawl O, pivoted to the easing E, and provided with teeth O and O2, for engaging with the teeth of the star-Wheel N, substantially as herein shown und described.

LEVIS BURVELL MCDONALD. 

